From 4fa96afd94a9bb29135d6e2e8fdb527e58f4fd5c Mon Sep 17 00:00:00 2001 From: Andre Przywara Date: Tue, 13 Jan 2015 12:02:13 +0000 Subject: [PATCH] arm/arm64: KVM: force alignment of VGIC dist/CPU/redist addresses Although the GIC architecture requires us to map the MMIO regions only at page aligned addresses, we currently do not enforce this from the kernel side. Restrict any vGICv2 regions to be 4K aligned and any GICv3 regions to be 64K aligned. Document this requirement. Signed-off-by: Andre Przywara Signed-off-by: Christoffer Dall --- Documentation/virtual/kvm/devices/arm-vgic.txt | 4 ++++ virt/kvm/arm/vgic.c | 16 +++++++++++++--- 2 files changed, 17 insertions(+), 3 deletions(-) diff --git a/Documentation/virtual/kvm/devices/arm-vgic.txt b/Documentation/virtual/kvm/devices/arm-vgic.txt index 5d4fd4b..3fb9054 100644 --- a/Documentation/virtual/kvm/devices/arm-vgic.txt +++ b/Documentation/virtual/kvm/devices/arm-vgic.txt @@ -20,20 +20,24 @@ Groups: KVM_VGIC_V2_ADDR_TYPE_DIST (rw, 64-bit) Base address in the guest physical address space of the GIC distributor register mappings. Only valid for KVM_DEV_TYPE_ARM_VGIC_V2. + This address needs to be 4K aligned and the region covers 4 KByte. KVM_VGIC_V2_ADDR_TYPE_CPU (rw, 64-bit) Base address in the guest physical address space of the GIC virtual cpu interface register mappings. Only valid for KVM_DEV_TYPE_ARM_VGIC_V2. + This address needs to be 4K aligned and the region covers 4 KByte. KVM_VGIC_V3_ADDR_TYPE_DIST (rw, 64-bit) Base address in the guest physical address space of the GICv3 distributor register mappings. Only valid for KVM_DEV_TYPE_ARM_VGIC_V3. + This address needs to be 64K aligned and the region covers 64 KByte. KVM_VGIC_V3_ADDR_TYPE_REDIST (rw, 64-bit) Base address in the guest physical address space of the GICv3 redistributor register mappings. There are two 64K pages for each VCPU and all of the redistributor pages are contiguous. Only valid for KVM_DEV_TYPE_ARM_VGIC_V3. + This address needs to be 64K aligned. KVM_DEV_ARM_VGIC_GRP_DIST_REGS diff --git a/virt/kvm/arm/vgic.c b/virt/kvm/arm/vgic.c index 184c6db..0cc6ab6 100644 --- a/virt/kvm/arm/vgic.c +++ b/virt/kvm/arm/vgic.c @@ -1683,6 +1683,7 @@ int kvm_vgic_addr(struct kvm *kvm, unsigned long type, u64 *addr, bool write) struct vgic_dist *vgic = &kvm->arch.vgic; int type_needed; phys_addr_t *addr_ptr, block_size; + phys_addr_t alignment; mutex_lock(&kvm->lock); switch (type) { @@ -1690,22 +1691,26 @@ int kvm_vgic_addr(struct kvm *kvm, unsigned long type, u64 *addr, bool write) type_needed = KVM_DEV_TYPE_ARM_VGIC_V2; addr_ptr = &vgic->vgic_dist_base; block_size = KVM_VGIC_V2_DIST_SIZE; + alignment = SZ_4K; break; case KVM_VGIC_V2_ADDR_TYPE_CPU: type_needed = KVM_DEV_TYPE_ARM_VGIC_V2; addr_ptr = &vgic->vgic_cpu_base; block_size = KVM_VGIC_V2_CPU_SIZE; + alignment = SZ_4K; break; #ifdef CONFIG_ARM_GIC_V3 case KVM_VGIC_V3_ADDR_TYPE_DIST: type_needed = KVM_DEV_TYPE_ARM_VGIC_V3; addr_ptr = &vgic->vgic_dist_base; block_size = KVM_VGIC_V3_DIST_SIZE; + alignment = SZ_64K; break; case KVM_VGIC_V3_ADDR_TYPE_REDIST: type_needed = KVM_DEV_TYPE_ARM_VGIC_V3; addr_ptr = &vgic->vgic_redist_base; block_size = KVM_VGIC_V3_REDIST_SIZE; + alignment = SZ_64K; break; #endif default: @@ -1718,10 +1723,15 @@ int kvm_vgic_addr(struct kvm *kvm, unsigned long type, u64 *addr, bool write) goto out; } - if (write) - r = vgic_ioaddr_assign(kvm, addr_ptr, *addr, block_size); - else + if (write) { + if (!IS_ALIGNED(*addr, alignment)) + r = -EINVAL; + else + r = vgic_ioaddr_assign(kvm, addr_ptr, *addr, + block_size); + } else { *addr = *addr_ptr; + } out: mutex_unlock(&kvm->lock); -- 2.7.4